Weaving machine for making fiberglass grating with improved tension control of fiberglass strands during layup

ABSTRACT

A weaving machine alternately lays catalyzed resin wetted fiberglass strands within respective right angle sets of uniformly spaced, open-ended intersecting slots within the upper face of a weaving form by driving reciprocating carriages mounted on rails via rotating wheels across the top of the form bearing said right angle sets of uniformly spaced, open-ended slots. A horizontal base plate supports hydraulic cylinders whose projectable and retractable piston rods suspend a running bar having horizontal apertures through which the fiberglass strands pass. After passage across the form, the running bar is dropped to force the wetted strands into aligned slots. Detents engage the strands at each side of the open slots. A hydraulic rotary motor has a rotary drive shaft in the form of a horizontal threaded rod passing through and engaging the threads of a horizontal tapped bore of a nut fixed to the carriage base plate. The hydraulic motor is rotated bidirectionally to reciprocate the carriages across the form. Resin tanks bearing resin wet the fiberglass strands prior to weaving, with the strands wrapped about the peripheries of three laterally adjacent, spaced, parallel tension bars within the tank. Tensioning is varied by raising or lowering the center tension bar to cause more or less wrapping of the strands about all three tensioning bars.

FIELD OF THE INVENTION

This invention relates to a weaving machine for laying catalyzed resinwetted fiberglass strands within right angle sets of uniformly spacedopen ended slots within an upper face of a weaving form, and moreparticularly to a weaving apparatus which provides uniform tension ofthe fiberglass strands during layup and which results in increaseddensity and uniformity of the fiberglass strands within the compressionmolded grating resulting therefrom.

BACKGROUND OF THE INVENTION

The present invention relates to an improvement within applicant'scompression molded fiberglass grating apparatus as set forth inapplicant's prior U.S. Pat. No. 3,772,126, issued Nov. 13, 1973. Theapparatus of applicant's prior patent requires initially a rectangularmetal block weaving form to be positioned on an underlying support witha top face bearing first and second sets of spaced parallel open endedslots, with respective sets of slots intersecting at right angles andweaving means for repetitive placement of continuous strands of resinwetted fiberglass alternately within respective slots of each set in azig-zag manner. Projectable and retractable detents provided on the format the open ends of the slots are engageable by the fiberglass strandsto facilitate zig-zag depositing of the strands in the slots with thedetents projected to hold the strands during the zig-zag layup andretracted to allow lay of the preceding layer of strands with spacedparallel slots.

In a true sense of the word, the strands are not woven, but arealternately layed in the slot, first in one direction and then in theopposite direction, with the detents acting at respective ends of theslots of the two sets, to hold strands at their overlapping reversingpoint at the end of the slots as they are filled into the slot, by theweaving machine running bar reversing direction, after the strandsengage respective detents.

The manner of operation of the apparatus of the '126 Patent involvesswinging a pair of substantially L-shaped weaving arms over the form indirections running respectively parallel to the slots of the two setssuch as from front to back of the rectangular block form for one set ofslots and from one lateral side to the other for the second set ofslots. In swinging of the arm through a 180° arc, to effect placement ofthe wetted strand within given parallel slots with the strands passingthrough spaced parallel apertures within the arms, the strands arerequired to follow a full 180° arcuate path to a maximum vertical heightat the center of the arc, significantly above the top of the formbearing the rectangular slots.

The applicant has found that such action inherently varies the tensionof the strands as they are deposited within the slots due to theexcessive travel of the strands about the arcuate path of the swingingarms. Additionally, while the wetted strands frictionally engage movableand static components of the apparatus such as the apertures within theswinging arm and apertures within the resin tank where they areinitially directed for wetting by the catalyzed resins prior to depositwithin the sets of slots, the tension set up during wetting has beeninadequate to insure uniform layup and achievement of desired density ofthe fiberglass reinforcing strands within the molded resin grating.

It is therefore a primary object of the present invention to provide animproved weaving machine for the making of a fiberglass reinforcedcompression molded grating, wherein the catalyzed resin wettedfiberglass strands are more quickly inserted within the sets of spacedparallel slots of the weaving form, wherein the wetted fiberglassstrands are subjected to continuous, uniform tension throughout thewetted strand insertion step, wherein tension on the strands may bereadily varied depending upon the nature of the catalyzed resins beingapplied to the fiberglass strands and wherein the depositing of thecatalyzed resin wetted strands in zig-zag fashion within the slottedform reduces the time span between wetting of the strands, weavingthereof into the grating form, transfer of the strands from the form tothe preheated female mold, and the compression and curing of the resinwithin preheated male and female mold halves at a downstream pressstation.

With the foregoing objects and features in view, and such other objectsand features which may become apparent from the specification, theinvention will be understood from the following description taken inconjunction with the accompanying drawings in which like numeralsdesignate like parts.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top plan view of a completed grating using the apparatus ofthe present invention.

FIG. 2 is a front elevational view of the improved weaving apparatus formaking a compression molded fiberglass reinforced resin grating forminga preferred embodiment of the present invention.

FIG. 3 is a side elevational view of the apparatus of FIG. 2.

FIG. 4 is a top plan view of the weaving machine of FIGS. 2 and 3.

FIG. 5 is an enlarged sectional view of the machine of FIG. 2, takenabout line 5--5 illustrating one spool support assembly thereof.

FIG. 6 is an enlarged side elevational view, partially broken away, ofone resin tank of the weaving machine.

FIG. 7 is a vertical sectional view taken about lines VII.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the drawings, FIG. 1 illustrates a completed fiberglassreinforced compression molded grating designated G, having a determinatesize, taking a rectangular plan form and consisting of one set of spacedparallel fiberglass strands 12 crossing with a second set of suchstrands 14 at an angle. In the illustrated Figure, the two sets ofstrands 12, 14 cross at right angles, but the angles may be acute orobtuse, as desired. The grating G is essentially that shown at FIG. 3 inthe prior '126 Patent. However, the invention has broader application toa weaving machine in which the spaced parallel catalyzed resin coatedfiberglass strands are not subsequently heated and compressed in a pressat a downstream station, but are caused to be set within a mass of curedresin without the compression of the wet fiberglass strands, althoughthe compression molded form of grating is preferred.

Similar to U.S. Pat. No. 3,772,126, the grating G is formed fromfiberglass strands by a weaving machine indicated generally at 10 in theFIGS. 2-4. The machine is constituted by an open frame indicatedgenerally at 16 formed about and in conjunction with a supporting table18, having a flat, horizontal table top 20 supported at opposite ends byvertical legs or risers 22. The use of table 18 is in a schematic sensesince its function is to stationarily support a rectangular, metal,parallelepiped weaving form indicated generally at 24. In actuality, theform 24 is preferably supported by wheels or rollers (not shown)positioned so as to move from right to left, FIG. 2 along laterallyspaced longitudinally extending rails (not shown) such that the weavingform 24 after receiving first and second sets of catalyzed resin wettedfiberglass strands 12, 14 alternately crossing with each other, is thenmoved to a downstream station where the weaving form is inverted and thewet strands forced to move out of the weaving form and into anunderlying female mold (not shown). Subsequent to that transfer thefemale mold cooperates with a vertically reciprocating male mold (notshown) at the press station, closing off the slots within the femalemold within which the wetted strands reside while subjectingsimultaneously the hot resin wetted strands to both heat and intensepressure by compression action of forces acting on the male and femalemold in a classic, heated compression mold process.

The present invention is directed to the initial weaving machine orapparatus at the first upstream, weaving station, as partially depictedin FIG. 1. As seen best in FIG. 4, which is a plan view of the weavingmachine, rectangular block (parallelepiped) form 24 has within a topface 26, one set of longitudinally spaced parallel, open-endedhorizontal slots 28, and a second set of spaced parallel, open-endedslots 30 which intersect the slots 28 at a desired angular relationship,in this case at right angles as shown. The table 18 is integrated intothe open framework 16 and for illustrative purposes that frameworkconsists of a series of vertically upright risers 32 and longitudinal,horizontal beams 34 joined thereto, For reinforcing purposes, and torigidify the frame, oblique reinforcing members 36 span between thevertical risers 32 and the horizontal beams 34. The open framework 16 isof elongated rectangular form, and vertical risers 32 at opposite sidesof the weaving machine 10 are joined by various transverse horizontalbeams 38. At an upstream end 40 of the machine, vertical risers 32support a transversely extending beam 42, particularly defining spoolsupport assembly 41 and which functions as a horizontal support for aplurality of spools 44 carried by vertical upright studs 46 affixed tothe beam 42 at longitudinally spaced positions along the length of thebeam 42. The spools 44 permit the unwinding of a strand 12 of fiberglassfrom the center of each spool. The fiberglass strands 12 are led to atransversely extending, upwardly open rectangular resin pan or resintank indicated generally at 48 which is fixed to and supported by theopen frame 16, particularly via a pair of horizontal beams 34 toopposite sides of framework 16 of the machine 10. The function of resinpan 48 is to wet the fiberglass strands 12 prior to their being woveninto the respective slots 28, within the upper face 26 of weaving form24. A second resin pan 48A is provided in the machine 10 for wettingstrands 14 prior to their being woven into crossing slots 30 within form24. In FIG. 2, principally the right side or upstream end components ofweaving machine 10 are illustrated in detail. Duplicate means are thusprovided at 41A for supporting other spools 44 of fiberglass forming thecross strands 14 to the rear of the form 24 from that illustrated inFIG. 2, along with the mechanism for effecting the weaving of thestrands 12 onto the form 24 and within the slots thereof as a substitutefor the oscillating generally L-shaped arms within the apparatus ofprior U.S. Pat. No. 3,772,126. Further, while a description will begiven of duplicate mechanisms of the weaving machine 10 which areincorporated within the machine 10 at right angles to the disposition ofthe spool support assembly 41, FIG. 2, and a reciprocating running barassembly indicated generally at 50, FIG. 2. The following description ofthe machine components for the laying of the strands 12 longitudinallywithin slots 28 of weaving form 24, i.e., the operation of assemblies 41and 50 of one-half of the weaving machine 10 are more detailed than tothe duplicate assemblies 41A and 50A disposed at right angles thereto.In assemblies 41 and 41A, as well as 50 and 50A, like elements are givenlike numerical designations. The same is true for the respective resinpans 48 and 48A, since it is the resin pans which include the variabletensioning means for the fiberglass strands 12, 14 as they are wetted bythe resin and prior to weaving of these strands back and forth withinrespective slots 28, 30 of the weaving form 24.

Upwardly open elongated resin pan 48 is adapted to receive strands 12which first pass through vertical guide slots 52 within the top of aguide bar 54 fixed to beam 42 and extending transversely over the fulllength of the beam 42 bearing the spools 44. Spools 44 are positioned atsome vertical height above the resin tanks 48, 48A to permit workers topass under the non-wetted strands for access to various parts of machine10. As the strands 12 are drawn off the center of the spools 44 undertension, they ride over or under one or more fixed cylindrical bars 56mounted to frame 16 intermediate of spools 44 and resin tank 48. Theresin tank 48 is provided with a catalyzed resin R to a level of threetransversely extending, parallel, relatively fixed tension bars orbreaker bars 58, 60 and 62, (from left to right) FIGS. 2 and 4. Thebreaker bars are of cylindrical rod form. In the illustrated embodiment,breaker bar 60 is mounted for vertical adjustment via small diameterthreaded rod extensions 60a at opposite ends which project throughselected horizontally aligned ones of vertical spaced oblique slots 61within opposed vertical risers 64, FIG. 6, internally of the resin tank48. In the illustrated embodiment, nuts 68 are threaded onto the rodthreaded ends 60a to hold the rod 60 at a desired height above thebottoms of the resin tank 48. The resin tanks 48 and 48A are completedby laterally opposed side walls 68, a front wall 70, a rear wall 72 anda bottom wall 74. The fiberglass strands 12 enter the interior of rightside wall 68, to the side proximate to the spools 44, via respectivesmall diameter holes 69 sized to the diameter of the strands 12, so thatthe presence of the strands 12 seals the holes, with the resin R abovethe holes 69. By raising the middle tension bar or breaker bar 60, thefiberglass strands 12 are forced to take a longer path and one whichwraps about a greater portion of the periphery of the three tension bars58, 60, 62, thus increasing the friction acting on the moving, wettedstrands 12, and thus increasing the tension of those strands as theypass through the resin tank 48. The wetted strands 12 next pass throughthe apertures 76 within a sizing bar 78, which is affixed to the top ofthe upper edge of the left side wall 68 of the resin tank 48. Inemerging from the mass of catalyzed resin R, the strands 12 arethoroughly soaked and coated with the resin. The sizing bar apertures orholes 76 are sized so that a surface coating portion of that resin Rcarried by the strands is prevented from passing through the sizing barapertures 76, and runs down over the right side of the sizing bar 76,FIG. 4, and across the horizontal base 80a of an L-shaped supportingstrip 80 which mounts the sizing bar 78 to the upper edge of the resintank side wall 70. The excess resin R drips from edge of the base 80aback into the interior of the resin tank 48. In passage to the sizingbar 78, the strands 12 ride over a fixed transverse cylindrical guidebar 82 adjacent the open top of the resin tank 48.

A second, principle aspect of the invention resides in the make up andoperation of the running bar assemblies 50 and 50A. Running bar assembly50 is illustrated in FIG. 2 to the right of the form 24 andlongitudinally aligned therewith and intermediate of table 18 and theportion of frame 16 supporting strand reels 44 on transverse beam 42.The companion running bar assembly 50A for inserting strands withinslots running front to rear within the top surface 26 of form 24 lies tothe rear of the Table 20 and to the rear of form 24, is oriented 90° tothe running bar assembly 50 and operates alternately to running barassembly 50. As mentioned previously, like elements in the twoassemblies are given like numerical designations. A more detaileddescription will be set forth herein with respect to running barassembly 50. The open frame 16 includes at least two vertical risers 32at the front and rear of the machine supporting at their upper end,transverse cross beam 84. Beam 84 supports mounting blocks 86 atopposite ends, which fixedly mount one end of horizontally extending,diamond-shaped cross-section rails 90. Rails 90 are of sufficient lengthto permit a carriage indicated generally at 100 to move in the directionof the longitudinal axis of the weaving machine 10 from a positionoriented at or beyond the left side 24a of the form 24 to a positionbeyond the right side 24b thereof. A second cross beam 85 mounted to theupper ends of riser 32, spans from front to rear. FIG. 4 and fixedlysupports the ends of rails 90 remote from motor 134 via mounting blocks86. The carriage 100 is comprised of a horizontal sheet metal carriagecross beam 109 such as steel which is of a length somewhat shorter thanthe distance between the front to rear spaced rails 90. The carriagecross beam 109 is welded at opposite ends or otherwise affixed to matingcarriage wheel housings 104. Wheel housings 104 are of rectangular openbox form, consisting of laterally opposed vertical walls 88, a top wall92 and a bottom wall 94. Projecting through the vertical walls 88 atpositions above and below rails 90 are pins or axles 108 which supportfor rotation thereon upper and lower matching sets of wheels 106 havingV-shaped peripheries. Wheels 106 are spaced vertically a distance equalto the thickness or vertical height of the diamond-shaped cross-sectionrails 90. The location of the wheels 106, mounted for rotation onrespective axles or pins 108, are illustrated in FIG. 2. As a result,the carriage cross beam 106 spans between the longitudinally directed,front to rear spaced rails 90 supported by upper and lower sets ofwheels 106 within carriage wheel housings 104. The carriage cross beam109 fixedly mounts a stationary nut 112 centered between the carriagewheel having a horizontal tapped axial bore 112a. Carriage assembly 100includes laterally spaced sidewalls 110 fixed at one end to outsidefaces of wheel housings 104 and at the opposite end to opposite ends ofcarriage base plate 102. Carriage base 102 is cantilever mounted nearopposite ends of the carriage cross bar 109 there are fixed respectivevertically upright hydraulic cylinders 114. Hydraulic fluid as indicatedby arrows 115, 117 is alternatively supplied and relieved from thehydraulic cylinder 114 via dual hydraulic fluid lines or hoses 116, 118,respectively. Projecting downwardly from the bottom of each hydrauliccylinder is a hydraulic cylinder piston rod 120, whose outer axial endis affixed to a horizontally extending metal running bar 122. Therunning bar 122 includes a series of longitudinally spaced, horizontalapertures or holes 124 which are sized to receive the strands 12 afterthey are wetted by resin R within the resin tank 48. The holes orapertures 124 constitute a horizontally aligned array through the centerof the running bar 122. As indicated by the double-headed arrow 125, therunning bar 122 may be raised or lowered by the selective application ofhydraulic fluid and removal of hydraulic from the hydraulic cylinders114. After passage through apertures 124, the wetted strands 12 whichinitially feed from the spools 44 have their free ends 12a projecteddownwardly between a horizontally movable clamping member 156 and afixed horizontal clamping bar or member 154 of a clamping bar assemblyindicated generally at 150, affixed to the end of a transverse crossbeam 156 mounted to vertical faces of front and rear risers 32 of theopen frame 16.

Clamping bar assembly 150, and its corresponding structure 150A havelike elements with like numerical designations. In this respect, theclamping bar assembly 150 includes horizontal cross beam 152 which formsa part of the open frame 16 and extends from the front of the machine,FIG. 2, to the rear. Mounted to the cross beam 152 is the stationaryclamping bar 154 which extends horizontally and transversely from frontto rear of the machine and at right angles to the longitudinal path oftravel of the carriage 100. Hydraulic cylinders 160 are mounted to thestationary clamping bar and each includes an extendable and retractablepiston rod 159 which projects axially outwardly of one end of thehydraulic clamping cylinder 160 at opposite ends of the stationaryclamping bar 154 and is fixed to movable clamping bar 156 via link 161.By selective application of hydraulic fluid to and removal from thehydraulic clamping cylinders 160, the shiftable clamping bar 156 ismoved toward and away from the stationary clamping bar 154. When thepiston rod is fully extended, gap G between the shiftable clamping bar156 and the stationary clamping bar 154 permits the free ends 12a of thestrands to pass by gravity between members 154, 156. Reversal ofhydraulic fluid flow through lines 162, 164 causes the retraction of thepiston rods 166 of the respective hydraulic clamping cylinders 160 tofrictionally clamp the free ends 128 of the strands. The clamping barassembly 150 is located at a vertical height somewhat below the slots 28within the form 24. With the running bar 122 in vertically raisedposition, just beneath the carriage plate 102a, the movement of thecarriage 100 along rails 90 to the left, FIG. 2, causes the wettedstrands 12 to be pulled out of the resin R within the resin tank 48 withthe free end 12a of the various strands clamped between movable clampbar 94 and the fixed clamping bar 96. A doubled back portion of each ofthe strands 12 occurs during passage of the carriage 100 from right toleft over the full length of travel from the right side 24b of form 24to the left 24a thereof as shown on dotted lines, FIG. 2.

That action is caused by operation of a hydraulic motor at 134 having athreaded output or drive shaft 136 threaded through nut 112 horizontalbore 112a. The hydraulic motor 134 is fixedly mounted to transversehorizontal beam or support 84 which also mounts blocks 86 for fixedlymounting one end of each of the rails 90. The drive shaft 136 terminatesremote from the hydraulic motor 134 in an idler bearing 140, whichrotatably supports a non-threaded terminal portion 136a of drive shaft136. The idler bearing 140 is fixedly mounted to the cross beam 84,which also supports mounting blocks 86 adjacent opposite ends thereofwhich in turn mount the ends of the rails 90 remote from similarmounting blocks 86 proximate to the hydraulic motor 134.

As may be seen in the various figures, particularly the top plan view ofFIG. 4, the spools 44 mounted to vertically upright studs 46 permit thestrands 12 to be drawn therefrom with their lengths aligned withrespective slots 28 by movement from right to left of the carriage 100which pulls the strands through the mass of resin R of resin tank 48with the strands 12 interleaved about the cylindrical, parallel,relatively fixed tension bars or breaker bars 58, 60 and 62. Theapparatus includes suitable microswitches or the like (not shown) tocontrol application and termination of the supply of hydraulic fluid tothe hydraulic motor 134 for effecting carriage movement, with thecarriage plate 102a to the right of or at the right vertical face 24b ofthe form 24 to a position at or beyond the left face 24a, and viceversa. With the strands 12 riding above the top 26 of the form 24, uponactuation of hydraulic cylinders 114, extension of the piston rods 120,causes the dropping of the running bar 122 to the left of vertical face24a of form 24, below the level of slots 28, thereby moving each alignedstrand 12 into a respective longitudinal slot 28. Unlike the weavingmachine or apparatus of my prior U.S. Pat. No. 3,772,126, the strands asshown in FIG. 2 of that Patent, do not take a circular arc path, asindicated by arrow 46 and the continuation thereof in dotted lines fromthe right side of the form, but reciprocate across the top of the openslotted form just above the slots 28. When the two hydraulic cylinders114 are actuated by feeding hydraulic fluid thereto as per arrows 115,and removal therefrom at 117, the piston rods 120 of those hydrauliccylinders extend thereby causing the portion of the strands 12 from thesizing bar 78 adjacent the resin tank 38, to the left side of the form24a, to move into the longitudinally extending slots 28 from one end ofthe form 24 to the other. A second portion of each strand 12 extendsfrom running bar 122 back to the clamping bar assembly 95. At thispoint, travel of the carriage 100 terminates prior to retraction ofpiston rods 120.

Selective operation of detents is then effected, in a manner which maybe identical to that of my prior U.S. Pat. No. 3,772,126. Those detentmechanisms or detent assemblies 170 are seen in FIGS. 2 and 5, andreference may be had to FIGS. 1 and 2 of the '126 Patent, that patentincorporated by reference herein. Specifically, each of the oppositelongitudinal vertical end faces 24a, 24b of form 24 as well as the frontand rear vertical faces 24c, and 24d, respectively, is provided with athin, rectangular cross-sectional slide bar 172 forming the principalmember of each detent assembly 170. These slide bars 172 are eachprovided with a series of horizontally spaced, elongated horizontalslots 174 within which are located small diameter horizontal pins 176which pass through the slots and which are fixed to a respectivevertical faces 24a, 24b, 24c, 24d of form 24. Hydraulic cylinders 178constitute fluid operators which effect selective, limited horizontalsliding of the slide bars 172. The hydraulic cylinders 178 are mountedto the top 20 of table 16 and are connected to a respective slide bar172. Each hydraulic cylinder 178 includes an axially extendable andretractable hydraulic cylinder rod 180, with a rigid arm 182 affixed tothe outboard end of the hydraulic cylinder rod 180, at right anglesthereto and fixed at its opposite end to the slide bar 172. Detents 184of inverted L-shaped configuration have vertical portions or fingers 184a extending upwardly from the slide bar 172, and terminate inhorizontal, right angle terminal portions 184b which are extendableacross the open ends of the longitudinal slots 28 and the transverseslots 30 (front to rear). When the slide bars 172 are slid in onedirection, as in accordance with my issued U.S. Pat. No. 3,772,126, thedetents 184 are disposed well to the side of the open ends of the slots28, 30; however, when a given slide bar 172 is shifted hydraulically inthe opposite direction on pins 176, limited by the length of thelongitudinally spaced horizontal slots 174, the horizontal detentterminal portions of detents 184 extend across the open ends of the slotabove the lower run of the strand from the clamping bar assembly 150 tothe vertical face of the form remote from that clamping bar assembly.Upon raising running bar 122 above the level of the form 24, returnmovement of carriage 100 from left to right, FIG. 1, causes the strands12 carried by the running bar 122 to wrap about detent portions 184 andmove into overlying position with the previously layed section of thestrands 12. During reverse movement of the carriage 100, with therunning bar 122 moving in a direction towards the resin tank 48, thereis no pulling of each of the strands 12 from its respective spool 44 ateach spool location. Rather, each of the wetted strands 12 arestationary as the running bar 122 reverses with the apertures or holes124 within the running bar moving over the wetted strands 12 until therunning bar 122 is to the right of vertical wall 24b of form 24, FIG. 2.Whereupon the hydraulic cylinders 114 are again supplied with hydraulicfluid to cause the hydraulic cylinder piston rods to extend outwardly ofthe hydraulic cylinders and to drive the running bar 122 from the fullline position, FIG. 2 vertically downwardly forcing the strands 12 to bereversely layed within their respective longitudinal slots 28. At thispoint, the detent assembly 170 proximate to vertical wall 24b of form 24is operated by supplying hydraulic fluid to the hydraulic cylinder 178of that assembly. The result is to cause the inverted L-shaped detents184 to shift from a position where the end of the slots 28 are open toone where the horizontal terminal portions 184b of the detents close offthat end of the slots. Each strand 12 is captured and awaits the nextmovement of the carriage from right to left, back over the top 26 ofform 24. In preparation for that movement, however, the hydrauliccylinders 114 of the carriage must be supplied with hydraulic fluid inthe opposite direction to retract the piston rods 120, raising therunning bar 122 well above the top surface 26 of form 24 so that thecarriage and the strand 12 carried thereby the running bar can move fromright to left over the form 24 for subsequent strand 12 portion depositin a repeat cycle after weaving of strands 14 at right angles to slotsby operation of running bar assembly 50A. As already discussed, thereare detent assembly slide bars 172 along the front and rear verticalfaces 24c, 24d of form 24, as well as horizontally along the verticalsurfaces 24a and 24b, and at right angles thereto. All four verticalsurfaces of the form are thus provided with detent assemblies 170.

As the detents 84 at the right hand end of form 24 are projected acrossslots 28 and the carriage 100 is moved to the left, the strands 12become hooked around the projected detents 184 at the right hand endsthereof, while, in the meantime, the detents at the left hand ends ofthe longitudinal slots 28 are moved to the side of those slots to permitdepositing of the next runs or stretches of strands 12 into slots 28.When the carriage 100 moves to the left side of form 24 beyond verticalface 24A, those detents 184 are shifted from slot free position todetent, slot closed position. The reversal of carriage movement ofcarriage 100 then occurs and the carriage 100 is driven to towards theleft side of the form 24 effected by reversal of rotation of hydraulicmotor 134.

When the back and forth movement of the carriage 100 has deposited twosuccessive stretches of strands 12 within the longitudinal slots 28,carriage 100 movement for running bar assembly 50 is terminated andmovement of carriage 100A and its running bar assembly 50A is initiated.As mentioned previously, identical components having identical numericaldesignations are employed in assembly 50A. Successive back to front andfront to back stretches or runs of strands 14 with their lengths alignedwith respective slots 30 are laid down in transverse slots 30 fromspools 44 located in line with those slots, after passage of strands 14through resin tank 38A for wetting of the strands 14. The carriage 100'of running bar assembly 50A effects deposit of two already successivestretches of strands 14 in slots 30 over laid up strands 12 at thejunctions or intersections of respective slots 28, 30.

Reference to FIGS. 3 and 4 illustrate the components of the nearduplicate running bar assembly 50A. The principal difference in therunning bar assembly 50A is the make up of the carriage 100A and therelative disposition and travel of that carriage 100A with respect tothe hydraulic motor, the cross bar supporting the same, and the use of asingle carriage base plate 102 supporting its running bar 122.Specifically, no physical interference, by the components of running barassembly 50, which is to the right of the form 24 to movement ofcarriage 100 from the rear of the form 24 completely across the slottedopen top 26 of the form and beyond the front vertical face 24c, and thenreturn beyond the rear vertical face 24d of weaving form 24. Threadeddrive shaft 136 extends over the area of form 24, supported by way ofhorizontal, rear beam 200 which is fixed via opposite mounting blocks 86to vertical risers 32 of the open frame 16, and a front horizontal beam202 extending parallel to beam 200 and being connected to beam 200 bylaterally spaced diamond shaped rails 90. Carriage plate 102 of carriage100A is similar to carriage plate 102 of carriage 100 of the running barassembly 50. To the rear of beam 200 is a further beam 204 which extendshorizontally, over a given longitudinal length of the machine 10 andsupports a number of reels 44 at longitudinally spaced positions on theupper surface thereof by way of upright studs or pintels 46. Beam 204 isalso part of the open frame 16, and is linked thereto by cross beam 206,FIG. 3. These elements form spool support assembly 41A from whichstrands 14 extend at respective spool locations in the direction offront to rear cross slots 30 within the upper face 26 of form 24.Strands 14 are led to resin tank 48A where the strands are wetted byresin R in the same manner as that occurring at resin tank 48 forstrands 12. After passage through the tank 48A and after tensioning bythe same tensioning mechanism as in resin tank 48, the strands 14 passthrough apertures 76 within sizing bar 78 of the resin tank 48A andthrough horizontal apertures 124 of running bar 122 which is mountedbeneath carriage plate 102, and which is raised and lowered by a pair ofhydraulic cylinders 114 mounted in vertically upright position toopposite ends of carriage base plate 102. The carriage 100A takes theform of a compact assembly in a plan view, FIG. 4 with a transversecross bar 206, FIG. 4, which fixedly mounts a nut 112 having a threadedhorizontal bore 112a through which projects a threaded drive shaft 136extending horizontally from hydraulic motor 134 of the running barassembly 50A. It is noted, in this case, that the threaded drive shaft136 terminates, in FIG. 4, beyond the front vertical face 24c of form24, the purpose of which is to allow the moving carriage 100A andrunning bar assembly 50A to reciprocate over the top 26 of form 24 fromthe pull line positions shown in FIG. 4, to the rear of form 24 tobeyond the front of that form as shown in dotted lines. Rails 90 extendbeyond horizontal beams 210 and 212. Beam 212 mounts under block 214rotatably supporting the end of threaded drive shaft 136, remote fromhydraulic drive motor 134.

In all respects, the operation of running bar assembly 50A of theweaving machine 10 is like that of running bar assembly 50 described ingreater detail. In this case, the initiation of movement of carriage100A from the rear of form 24 in the direction of the front of the form24, the termination of that movement and its reversal, along with theoperation of respective detent mechanisms or assemblies 170 on the frontface 24c and rear face 24d of the form 24 are effected in a similarmanner as discussed in detail with respect to running bar assembly 50 atcarriage 100.

Additionally, in the same manner as is effected for strands 12, aduplicate clamping assembly 150A is employed for clamping the free ends14a of the fiberglass strands 14 during repetitive back and forthmovements of carriage 100A, alternated with fore and aft movements ofcarriage 100 at right angles thereto for successive side to side andback to front runs of respective strands 12, 14. Selective, timedoperation of the detent assemblies 170 capture the ends of the strands14 laid down in slots 30 facilitating the maintenance of the strands 14in position and the proper tensioning of the wetted strands duringzig-zag lay down within the slots 30 of the form 24.

This completes one cycle of operation in a similar manner to thatdescribed in detail in my U.S. Pat. No. 3,772,126, which differsprincipally in the nature of the basic weaving elements specifically therunning bar assemblies 50 and 50A and the resin tanks 48 and 48A withthe tensioning means for the wetted strands 12, 14. The weavingprocedure is repeated by alternate actuation of carriages 100 and 100A,and running bar assemblies 50, 50A respectively, until the slots 28, 30are filled with stretches or runs of wetted, tensioned strands 12, 14 upto the level of the detent horizontal terminal portions 184b. Thestrands 12, 14 in the slots are then severed from the portions emanatingfrom spools 144, where the strand free ends 12a and 14a pass through theclamping bar assemblies 150, 150A. This must be accomplished so that theform 24 can be moved from the weaving station table 18 prior to transferof the woven grating G from the form 24 to the compression mold. Thatoperation is in accordance with the description within my earlier U.S.Pat. No. 3,772,126. Preferably the form 24 is mounted on rails (notshown) and moved from the position shown in FIG. 2 further to the leftwhere it is rotated so as to dump the wetted strands from the slots 28,30 of the form into mirror image slots within the upper face of a bottomfemale mold half at a compression molding station (not shown).

While it is preferred to wet the fiberglass strands 12, 14 in the tanks38, 38A prior to handling of the strands by the weaving machine runningbar assemblies 50, 50A, it is possible, utilizing the apparatus of thepresent invention, to weave the fiberglass strands in a dry conditionand to transfer the dry grating preform into the mold from the form 24.In such case, the fiberglass strands are wetted in the mold forsubsequent compression and curing.

While in the foregoing there has been described and shown a preferredembodiment of the invention, various modifications and equivalents maybe resorted to without departing from the spirit and scope of theinvention as claimed.

What is claimed is:
 1. In an apparatus for making a grating of adeterminate size from fiberglass strands and including a parallelepipedweaving form provided on an upper face thereof with one set of spacedparallel, open-ended slots, and a second set of spaced parallel,open-ended slots intersecting the slots of the first set at anangle,means for depositing sets of fiberglass strands in a zig-zagmanner in respective slots alternately crossing each other at theintersection of the slots, detent means engageable with the fiberglassstrands at the end of the slots to facilitate zig-zag depositing of thestrands in the slots, and means for projecting and retracting saiddetents across the open ends of the slots coordinated with the means fordepositing sets of fiberglass strands within respective slots, theimprovement wherein: said depositing means comprises carriages, andmeans for supporting said carriages above and to respective right angleintersecting sides of said parallelepiped form for reciprocatingmovement selectively over the upper surface of said parallelepiped form,means for supporting said sets of fiberglass strands on said carriagesfor movement across the top of the parallelepiped form with theirlengths aligned with respective slots, means for raising and loweringsaid fiberglass strands across their lengths vertically with respect tosaid form for selectively positioning of said aligned fiberglass strandsin respective sets of slots at the end of travel of said reciprocatingcarriage for capture therein by said detent means, and motor means fordriving said carriages alternately across said form, from one side tothe other to alternately deposit said sets of fiberglass strands in azig-zag manner in respective slots.
 2. The apparatus as claimed in claim1, wherein said carriage supporting means include rails extendingparallel to opposite sides of said parallelepiped form towards and awayfrom said form,said carriages each include: a horizontal carriage crossbeam, carriage wheel housings fixedly mounted to opposite ends of saidcarriage cross beam, sets of wheels rotatably mounted for rotation abouthorizontal axes within said wheel housing and engaging respective rails,a carriage base plate of a length generally corresponding to the lengthof the carriage cross beam, fixed to said means for mounting a runningbar horizontally beneath said carriage base plate for movementvertically towards and away from the carriage base plate, longitudinallyspaced apertures within said running bar slidably receiving saidfiberglass strands, at positions corresponding to the spacing ofrespective slots within said parallelepiped form, and being in alignmenttherewith, and means caused by said carriage base plate for selectivelyraising and lowering said running bar with respect to said carriage baseplate, and wherein said carriage is vertically positioned with respectto said form such that with said running bar in vertically raisedposition, said carriage is free to move across the top of saidparallelepiped form, whereby weaving operation is effected byalternately reciprocating carriages of respective running bar assembliesacross said form and deposition of said strands by selectively loweringsaid running bars beneath said carriage base plates after termination ofcarriage movement from one side of the form to the other to facilitatesaid zig-zag depositing of the strands in said slots, and engagement ofthe detent means with said deposited strands in coordination with themovement of respective carriages.
 3. The apparatus as claimed in claim2, wherein said carriage wheel housings are of hollow, rectangular crosssection, including laterally opposed side walls and top and bottomwalls, and wherein said set of wheels comprises at least one upper andlower wheel mounted for rotation about horizontal axes by axlesprojecting between the side walls of the carriage wheel housing,whereinsaid wheels have V-shaped grooves at the peripheries thereof, whereinsaid rails are of diamond-shaped cross section, and wherein said wheelsare sized and positioned such that the V-shaped grooves in theperipheries thereof respectively engage the tops and bottoms of saiddiamond shaped cross sectional rails.
 4. The apparatus as claimed inclaim 1, wherein said means for driving said carriages comprise astationery rotary hydraulic motor in juxtaposition to said rails andsaid carriage,said rotary hydraulic motor includes a rotatably driven,horizontal, elongated threaded drive shaft, said carriage cross beamfixedly mounting a nut having a horizontal threaded bore, sized to thediameter of said threaded drive shaft, said threaded shaft passesthrough said horizontal threaded bore of said nut and is in meshtherewith, such that upon supplying of hydraulic fluid to said hydraulicmotor in reversible fashion, said motor rotates bidirectionally to causesaid carriage to be driven bidirectionally across the top of saidparallelepiped form.
 5. The apparatus as claimed in claim 1, whereinsaid apparatus further comprises means for applying catalyzed resin tosaid fiberglass strands prior to depositing said strands in said openended slots of said form,wherein said means for applying catalyzed resinto said fiberglass strands comprises a resin tank in fixed juxtapositionto said movable carriage means and to the side of said carriage meansremote from said form, wherein said tank includes at least threelaterally spaced, parallel cylindrical tension bars within said tankfixedly positioned and extending transverse to the path of movement ofsaid fiberglass strands through said tank, wherein said fiberglassstrands are partially wrapped about said plurality of tension bars, andwherein at least one of said tension bars is vertically adjustable withrespect to the others to permit said fiberglass strands to wrap about agreater or lesser portion of the periphery of the laterally adjacenttension bars, thereby varying the friction acting on the movingfiberglass strands moving through said resin tank to vary the tension onsaid strands during wetting within said resin tank.
 6. The apparatus asclaimed in claim 5, wherein said resin tank comprises an upwardly opentank extending transversely across the path of movement of said strands,said tension bars comprise three in number, positioned side-by-side,andwherein said tank includes a vertical riser at each of opposite endsof a middle tension bar of said three bars and means for selectivelyfixedly mounting said middle tension bar at one of varying heights onsaid tank vertical risers and extending horizontally therebetween. 7.The apparatus as claimed in claim 6, wherein said tension bars are inthe form of cylindrical, relatively small diameter cylindrical rods. 8.The apparatus as claimed in claim 5, wherein said tank includes sidewalls extending perpendicular to the direction of movement of thestrands across the tank and in contact with said tension bars,andwherein horizontally aligned spaced apertures are provided within oneof said side walls of the tank at positions generally below the level ofresin therein, and wherein the apertures are sized relative to thestrands so that the strands in moving through the apertures self-sealthe apertures to prevent resin escaping from the interior of the tankthrough said apertures.